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排序方式: 共有171条查询结果,搜索用时 15 毫秒
81.
Lucineide Balbino da Silva Marcelo Massayoshi Ueki Marcelo Farah Vitor Manuel Coelho Barroso João Manuel Luis Lopes Maia Rosario Elida Suman Bretas 《Rheologica Acta》2006,45(3):268-280
Blends of polyethylene terephthalate (PET) with a liquid crystalline polymer (LCP) and a compatibilizer were produced by twin
screw extrusion and injection molding. Transesterification and compatibilization studies were made in a torque rheometer.
The morphology of the injection-molded plaques was studied by scanning electron microscopy. The blends shear growth function
was measured in a cone and plate rheometer. The elongational growth function
was measured in a modified rotational rheometer. Transesterification was observed in the PET/LCP/compatibilizer 95/5/0 blend.
The injection-molded plaques displayed the usual “skin-core” morphology. All the blends were highly shear-thinning, even at
low shear rates; thus, a zero-shear viscosity could not be calculated. The compatibilized blend had the highest shear viscosity
of all the blends, confirming the strong PET/LCP interphase and the effectiveness of the compatibilizing agent. On the other
hand, the 90/10/0 blend had the lowest shear viscosity. All the blends showed strain softening behavior, similar to the PET.
The 90/10/0 blend had the highest elongational growth function, while the 95/5/0 had the lowest. The compatibilized blend
had an intermediate behavior between both blends. 相似文献
82.
Sei-ichiro Ueki 《Integral Equations and Operator Theory》2016,84(1):89-104
In this paper, we give a characterization for the Fock-type space \({\mathcal{F}_{\alpha}^{\infty}(\mathbb{C}^N)}\) in terms of higher order derivatives of f and behaviors of local integral means of those derivatives. The space \({\mathcal{F}_{\alpha}^{\infty}(\mathbb{C}^N)}\) has the closed subspace \({\mathcal{F}_{\alpha, 0}^{\infty}(\mathbb{C}^N)}\). We also characterize this subspace via higher order derivatives. As an application we study the boundedness and compactness of the extended Cesaro operator T g on \({\mathcal{F}_{\alpha}^{\infty}(\mathbb{C}^N)}\) and \({\mathcal{F}_{\alpha, 0}^{\infty}(\mathbb{C}^N)}\). 相似文献
83.
Tetsu Ito Takehiko Tawara Hiroshi Yamaguchi Mineo Ueki Kouta Tateno Satoshi Mitsugi Hideki Gotoh Eiichi Kuramochi Masaya Notomi 《Photonics and Nanostructures》2006,4(2):89-93
We fabricated photonic-crystal (PhC) microcavities tuned to GaAs quantum dots (QDs) formed by interface fluctuation for the first time and observed the spontaneous emission enhancement in a weak coupling regime. A QD is a very thin GaAs quantum well (QW), and its interface steps exhibit quantum dot-like behavior. The emission intensity from the PhC cavity was stronger than that from the area where no PhC pattern was fabricated and the overall shape of the photoluminescence (PL) agreed with the cavity mode calculated with the three-dimensional (3D) finite-difference time domain (FDTD) method. The spontaneous emission enhancement factor was 10. 相似文献
84.
A. Takahashi S. Igarashi Y. Ueki H. Yamaguchi 《Analytical and bioanalytical chemistry》2000,368(6):607-610
A homogeneous liquid-liquid extraction method for 36 metal ions with diethyldithiocarbamate was studied. As a result, 11 metal ions were extracted as metal-chelates. Under the experimental conditions, the maximum concentration factor was 500 (i.e., 0.1?mL of sedimented liquid phase was produced from 50 mL of aqueous phase). Moreover, the proposed method was utilized as a preconcentration method for X-ray fluorescence analysis of these metals. The recovery of each metal was ca. 97–100%. All calibration curves were linear over the range of 5.0 × 10–7 mol L–1 to 1.0 × 10–5 mol L–1. The detection limits were at the ¶10–8 mol L–1 levels and the relative standard deviations were below 5% (5 determinations). When the proposed method was used for the determination of contaminants in a synthetic sample (Al-based alloy model) and of components in an Au-Pd alloy, the results were satisfactory. 相似文献
85.
86.
Rajamani Rajmohan Geoffrey Vrla Hisanori Ueki Kappamveettil Sajna Toshiaki Takei Hiroyoshi Ohtsu Masaki Kawano Pothiappan Vairaprakash Kentaro Tashiro 《化学:亚洲杂志》2020,15(6):766-769
Self‐assembly of a series of dimetallic sequences constructed on a backbone with two successive tyrosine moieties ( Fmoc‐M 1 ‐M 2 ‐CO2H ) revealed that the resultant morphology is clearly dependent on the metal sequence, where Re‐containing sequences such as homometallic Fmoc‐Re‐Re‐CO2H specifically afforded amyloid‐like nanofibers. These findings further allowed to achieve the fibrillation of a longer metal sequence containing three different metals ( Fmoc‐Rh‐Pt‐Re‐Re‐CO2H ). Cyclic voltammetry of the fibrillated Fmoc‐Re‐Re‐CO2H demonstrated that the redox activity of the metal complexes in the sequence is preserved in the nanofibrous forms. 相似文献
87.
Poly(benzyl methacrylate) (PBzMA) and its copolymers exhibit lower critical solution temperature (LCST)-type phase separation in common hydrophobic ionic liquids (ILs) such as 1-ethyl-3-methylimidazolium bis(trifluoromethane sulfone)imide ([C(2)mim][NTf2]). The turbidity measurements for PBzMA/IL mixed systems reveal that the LCST-type phase separation temperatures change significantly with the changes in the chemical structures of polymers and ILs. Moreover, cross-linked PBzMA gels show reversible and discontinuous volume phase transition in [C(2)mim][NTf2] with the changes in temperature. 相似文献
88.
The cytochalasin class of fungal metabolites was analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in microbial extracts. ESI-MS analyses of reference cytochalasins were performed and several product ions were produced in MS/MS experiments on parent ions that are structurally characteristic. A precursor ion search was performed to detect cytochalasins in an ethyl acetate extract of fungal strain RK97-F21. Three cytochalasins were detected and one of the components was identified as epoxycytochalasin H by comparing the tandem mass spectra of the product ions with those of reference compounds. This finding was further validated by LC/MS and LC/MS/MS experiments. 相似文献
89.
90.
Sei-ichiro Ueki 《Proceedings of the American Mathematical Society》2007,135(5):1405-1410
We characterize the boundedness and compactness of a weighted composition operator on the Fock space. Our results use a certain integral transform. We also estimate the essential norm of a weighted compositon operator. The result could be extended to the higher-dimensional case.